Modern vehicles include an array of vehicle electronics that facilitate vehicle functions. For example, the vehicles can include electronic control units (ECUs), vehicle sensors, vehicle telematics units, infotainment head units, and memory devices, to name a few examples. These elements generally exchange data over a vehicle bus as part of collectively executing different vehicle functions. In addition, the vehicle electronics may include an outward-facing data port that permits connection with an external computing device. On one hand, the data port can helpfully grant a service technician the ability to upload software updates to the vehicle electronics or download information, such as diagnostic trouble codes (DTCs), that can be used to improve vehicle operation. On the other hand, the data port may also permit unauthorized users to access the vehicle electronics as well.
Vehicle electronics may include a number of defensive mechanisms to deter unauthorized access to vehicle busses. But improvements to those defensive mechanisms may be developed after the design of vehicle electronics has been determined and/or a significant number of vehicle electronics components have already been assembled. In that event, it can sometimes be difficult if not impossible to retrofit the vehicle electronics components with updated defensive mechanisms. Thus, it would be helpful to implement a dynamic device that can regulate data communications between the vehicle electronics and an external computing device and be physically located in the data port path between them.